Printing-block



(No Model.)

J. R. & G. W. CUMMINGS.

PRINTING BLOCK.

No. 351,313. Patented Oct. 19, 1886.

WITNESSES,

ll'iairnn TATES JOH). It. CUMMINGS AND GEORGE \V. CUMMINGS, OF CHICAGO, ILLINOIS.

' PRINTING-BLOCK.

SPECIFICATION forming part of Letters Patent No. 351,313, dated October 19, 1886.

Application filed March 2, 1886.

To all whom it may concern.

Be it known that we, JOHN R. CUMMINGS and GEORGE \V. CUMMINGS, citizens of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Printing-Blocks; and we do hereby declare the following to be a full, clear, and exact description of theinvention, such as will enable others skilledin the art to which it appertains to make and use the same.

Our invention relates to the means for securing electrotype and other printing shells or very thin plates to bases or blocks; and it con sists of an improvement in the matter patented to Albert IV. Marshall, February 17, 1885, No. 312,569, and to us March 10, 1885, No. 313,812. The subject of the.t'ormer-1nentioned patent is a printing-shell without the ordinary backing, and provided with marginal flanges to adapt it to asuitable block, and the latter mentioned patent covers a base-block, the upper surface of which is even and plain, with grooves formed parallel and contiguous to the upper edges thereof, into which the marginal flanges of the plate are adapted to enter to secure the same in position. Some difficulty has been found in structures made precisely as shown in these patents in holding the plate in place in the column, as the shell without other fastenings has been inclined to slip lengthwise on the base.

To overcome this difficulty is the object of our present invention; and to this end it consists in forming projections or teeth upon the upper edge of the base by punching, casting, or otherwise, for the purpose of preventing the shell from slipping when clamped thereon.

The invention is illustrated in the accompanying drawings, in which Figure l is a front elevation of our improved block; Fig. 2, a

plan; Fig. 3, a front elevation of the base with a shell applied thereto, and Fig. l a detail view of a modification.

Referring to the drawings, A represents a base or block having the grooves 1) formed therein parallel and contiguous to the upper edges, and c the projections or teeth formed thereon.

D is the thin platehaving the flanges c adapted to enter the grooves I).

The method of using our invention is as follows: The shell is placed on the base and a clamping-tool applied, which bends the edges over the teeth 0 and into the grooves b, and which operation forces the teeth into the flanges of the shell, making it impossible for the shell to move on the base. To form the teeth we take a suitable punch, and punch down from the top small sections of the edges of the base, as shown, which can be done very rapidly and with little expense; but similar holding'proj ections might be formed in other ways. It is possible, also, to hold the shell on the block to some extent by nicking the plain surface of the block, or its sharp edges, or roughing the inner sides of the grooves b, as shown in Fig. 4; but there are serious objections to all these plans, and we therefore prefer the means substantially as herein shown and claimed.

One advantage of our improvement is that it stretches the shell more tightly across the base than has been done heretofore, and the teeth being near the upper edge of the groove do not come in contact with the sharp instrument used for stripping the shell off, and are therefore protected from the wear, which is unavoidable in other devices of this character.

It is obvious that the base may be made of any material, though we prefer iron or steel, and when the metal is such that the teeth cannot be punched out such as cast-iron) they can be cast.

Having thus fully described-our invention, what we claim is A printing-block provided with teeth or projections along its surface and at or near its upper edges, for holdingaprinting-plate thereto, substantially as described.

In testimony whereof we aftix our signatures in presence of two witnesses.

J OHN It. CUMMINGS. GEORGE IV. CUMMINGS.

IVitnesses:

Gno. P. SMITH, HENRY SULLIVAN. 

